Migration is helping Africa in many ways

“WHAT’S NIGERIA’S second city?” asks Ngozi Okonjo-Iweala, an irrepressible economist and former finance minister of Nigeria, before chuckling: “London!” She is exaggerating (about 200,000 people who were born in Nigeria live in Britain) but she has a point: one of the most powerful trends shaping Africa, and the wider world, is migration. There are three different types: to the West, within Africa and from countryside to city. All are helping make the continent richer and better educated.